Counterpoised supporting device



March 18, 1969 T. F. sMn-H COUNTERPOISED SUPPORTING DEVICE Sheet l of 2Filed Jan. 4, 1967 INVENTOR. THOMAS E. SMITH 6AM, KM ,/W 7")4f/'0rn (yfVIII/I March 18, 1969 T. F. SMITH COUNTERPOISED SUPPORTING DEVICE Sheet0f 2 Filed Jan. 4. 1967 INVENTOR. THOMAS F'.. SMITH United States PatentO 12 Claims ABSTRACT OF THE DISCLOSURE A `supporting device having acounterpoised, elongated arm assembly with an upper end mounted to adownward facing supporting surfa-ce and a lower suspended end adapted tohold a tool and movable between raised and lowered positions. A spring-member is arranged at the upper end of the arm assembly to provide abalancing force so that the tool holding end is normally in the raisedposition. The arm assembly is mounted for movement about an axisperpendicular to the supporting surface and has a clamping device tolock the arm in a selected position relative to the perpendicular axis.A second clamping device is operable to lock the tool in a selectedorientation relative to the supporting surface.

Backgronnd of the invention This invention relates to supporting devicesand more specifically to an elongated supporting arm assembly having anupper end mounted for pivotal and swiveling movement relative to asupporting surface. The opposite end of the supporting arm is adapted tocarry a tool which may be locked or maintained in a predeterminedorientation relative to the supporting surface. The arm assembly iscounterbalanced so that the tool is suspended in a spaced positionrelative to a working surface.

Balanced supporting arm assemblies are useful for suspending tools suchas X-ray units, dental tools, and the like and are normally arranged sothat the user may swing the tool into a working position when in use andthen swing the tool out of the way when its use is not required.Conventional balanced supporting assemblies employ a balancingarrangement wherein a spring-biased member is mounted to provide a forceon the supporting arm assembly in opposition to the weight of the armassembly and the tool which is attached thereto. Thus, the tool issuspended in the air and movable between positions toward and away froma working station. An example of a support of the prior art illustratingthe above features is disclosed in Patent No. 2,837,307 issued June 3,1958 to G. W. Schwager et al.

One feature necessary in balanced supporting arms is the ability to lockthe tool in a predetermined orientation relative to the supportingsurface and to maintain this orientation as the tool is swung into andout of a working position. In addition the tool supporting means mustpermit the orientation of the tool to be readily changed. These featureshave been partially achieved in the prior art by utilizing aparallelogram form of linkage having a suspended tool holder arranged toremain at a constant orientation relative to the supporting surfacethroughout the full arc of the arm assembly. However, such prior artdevices normally require an elaborate, cumbersome, mechanical means forestablishing the supporting arm in all of its various positions.

Summary The preferred embodiment of the present invention, which will besubsequently described in detail, solves the aforementioned problem andin addition provides `some special advantages for suspending a tool at awork station. The preferred embodiment is described with referice enceto a food mixing appliance and is useful in suspending such an appliancein the kitchen preferably to the under side of a cabinet or the like.

The utility of the present invention manifests itself Iby suspending themixing appliance in a raised position so that the user does not have tobear the weight of the appliance. In addition, the appliance issuspended by the supporting arm such that it is movable toward and awayfrom the other side of the supporting surface. Normally the appliance issuspended in a raised position adjacent the supporting surface so thatit is out of the Way of the user. It can be lowered by a slight downwardforce so that the working elements of the appliance come into engagementwith the contents -of the mixing bowl.

The preferred embodiment includes an elongated arm assembly, means foranchoring one end of the arm assembly to the supporting ysurface andmeans for attaching the appliance to the opposite end of the armassembly. The anchor means includes a pivot supporting the arm assemblyfor movement about a horizontal axis. The pivot is mounted in a novelspring loaded clamping arrangement that permits rotation of the armassembly in its raised position, but prevents rotation in the loweredworking position of the tool.

One preferred form 'of the supporting arm assembly comprises aparallelogram type of linkage including a pair of spaced apart parallel`supporting arm members and an elongated stabilizing arm member. Thefree end of the stabilizing arm is pivotally attached to the toolsupporting member. The supporting arms are also pivotally connected tothe tool supporting member by a pin arranged to clamp the toolysupporting member rigidly between the supporting arms so that the armassembly forms a rigid unit.

Another preferred form of the present invention contemplates atelescopic arm assembly which may be locked at a selected extendedposition. The tool holder is pivotally attached to the unsupported endof the arm assembly for movement about a horizontal axis. A rod,supported for rotation about an axis parallel to the longitudinal axisof the arm assembly, has a pair of gears, one at each end. One gearmeshes with a toothed section of the tool holder and the opposite gearmeshes with a toothed sector of the supporting lug. Raising and loweringof the arm assembly causes the rod to rota-te and pivot the tool holderthroigh an angular displacement compensating for the swing of the arm sothat the tool remains constantly oriented relative to a fixed workingsurface.

Preferably, the tool holder has an electrical jack coupled with the toolwhich permits rotation of the tool holder relative to the supporting armwithout the problem of entangling electrical lines.

It is, therefore, an object of the present invention to provide animproved counterbalanced, supporting arm assembly having an elongatedarm unit with one end pivotally mounted to a supporting surface by areleasable clamping connection and the other end adapted to carry anappliance for movement between spaced positions toward and away from thesupporting surface.

It is another object of the present invention to improve balanced armassemblies by providing means for clamping a tool supporting member in aselected orientation relative to the supporting surface.

It is a still further object of the present invention to improvebalanced arm supporting devices by providing such a device having an armunit which carries -a tool supporting member having a coupling forsupportably engaging the tool and which furnishes a connection from asource of electrical energy to the tool.

Still another object of the present invention is to increase the utilityof suspended arm assemblies wherein the tool may be moved through arcsof varying radii relative to the mounting connection by providing anextensible arm assembly comprising a pair of telescopically associatedarm sections.

It is -a still further object of the present invention to :provide aba'lanced supporting arm assembly which. carries a selforientingappliance holder.

Still another object of the present invention is to provide an armrassembly having a rst end pivotally attached to a supporting surface,an opposite tool-supporting end, and means for self-orienting a toolrelative to the supporting surface as the arm pivots toward and awayfrom the supporting surface by providing a shaft member supported forrotation by the arm unit and having an upper end engaged with thesupporting bracket to produce rotation responsive to relative movementbetween the arm and supporting surface, and the lower opposite endengaged with the tool holder and operative to produce a complementarymovement between the tool holder and the supporting surface.

Still further objects and advantages of the present invention willreadily occur to one skilled in the art to which the invention pertainsupon reference to the following detailed description.

Brief description ofthe draifvngs The description makes reference to thefollowing drawings in which like reference characters refer to likeparts throughout the several views and in which:

FIGURE 1 is a perspective view illustrating a preferred arm assemblymounted to the underside of a supporting surface and movable toward andaway from a raised position illustrated in phantom;

FIGURE 2 is an elevational view of the supporting arm assemblyillustrated in FIGURE 1 as seen substantially from the tool holderlooking toward the arm as sembly with parts in section for purposes ofclarity;

FIGURE 3 is a view of the Vpreferred arm assembly illustrated in FIGURE1 in its extreme lowered position,

FIGURE 4 is a modified form of the arm assembly illustrated in FIGURE 1with the appliance holder adapted for transmitting electrical energy tothe appliance;

FIGURE 5 is a modified embodiment of an arm as sembly illustrating thepresent invention;

FIGURE 6 is an enlarged, fragmentary, transversw sectional view takenalong lines 6-6 of FIGURES 5; and

FIGURE 7 is a sectional view taken along line 7-7 of FIGURE 5.

Description of the preferred embodiments Now referring to FIGURES 1-3,the improved supporting device comprises a pair of annular plates 10 and12 mounted by threaded fasteners 14 to the underside of a cabinet 16. Acircular supporting plate 18 is disposed in the opening defined by theannular plates 10 and 12 and carries a plurality of lips 20. The lips 20are slidably disposed in an annular slot dened by plates 10 and 12. Alug member 21 depends downwardly from the plate 18 and is provided withan aperture 22 adjacent the plate 10.

An annular locking ring 23 is xed to the plate 12 and has downwardlydirected teeth which are adapted to mesh with the teeth of a companionlocking ring 24. The locking ring 24 is adapted to be engaged with orreleased from the locking ring 23 and has an elongated flat springmember supported thereto at diametrically opposite lower portions. Themidportion 28 of a spring 26 extends through the aperture 22 in the lug21 and has a width slightly less than the width of the aperture 22. Theaperture 22 is dimensioned to permit the midportion 28 of the spring 26to freely flex therein. The lug 21 can be rotated relative to themounting plate 12 by lifting the locking ring 24 away from the lockingring 23 rotating the lug 21 to any desired orientation and thenpermitting the locking ring 24 to snap into engagement wtih the fixedlocking ring 23 to prevent the lug from rotating.

A pair of arm sections 30 are pivotally attached to the lug 21 by a pin32. The arm sections 30 each have an upper end portion 34 which areslightly bent towand one another and contoured to engage the springmember 26 adjacent its midportion 28 when the arm sections 30 are in alowered position.

An appliance holder 36 is sandwiched between the free ends of thesections 30 and has a thickness slightly less than the normal spacingtherebetween.

A pivot means 37 connects arms 30 to the appliance holder 36.

An elongated stabilizing arm member 38 is also disposed between the armsections 30 with an upper end pivotally attached by a pin 40 to the lug21 and its lower opposite en'd attached for pivotal movement to theappliance holder 36 by a pin 42. The arm sections 30 and the stabilizingarm 38 have a length chosen so that with lthe lug 21 and the applianceholder 36 they constitute a parallelogram type of linkage. The arms 38yand 30 can be pivoted between raised and lowered positions relative tothe cabinet 16 so that appliance holder 36 maintains a constantorientation relative to cabinet 16 in all positions of arms 30 and 38.

The pivot means 37 comprises a cooperating female pin element 44 and amale pin element 46. The female pin elment 44 has an enlarged head andis fixed to one of the arm sections 30 so that an internally threadedsection extends between the arm sections 30. The lmale pin element 46 isthreadably engaged with the female 'section 44 and has an outer enlargedend 48 in abutment with the companion arm section 30. The enlarged end48 terminates in a handle section 50.

By rotating the handle section 50 in a counterclockwise direction asviewed in FIG. 3, the male and female pin elements 44 draw the armsections 30 toward one another so that they clamp the appliance holder36 between them to form a rigid arm unit at any selected inclinationrelative to the cabinet 16. By rotating the handle 50 in the oppositedirection, the arm direction, the arm isections 30 are separated fromthe applicance holder 36 so that it may be pivoted about its clampingpin elements 44 and 46.

As thus far described, it is obvious that the improved supporting devicemay be swiveled in an arc of 360 about an axis generally normal to thesupporting surface provided by the cabinet 16 by raising the arms 30 sothat upper ends 34 disengage spring 26 thereby permitting the separationof locking rings 23 and' 24. Lowering of the arms 30 engages rings 23and 24 so that the arm assembly is locked in place. The appliance holder36 may be swung toward or away from the cabinet 16 and locked at yanyselected lowered position by the cooperating locking pin elements 44 and46.

The appliance holder 36 is preferably provided with a bent end section52 carrying a plurality of stepped sections arranged in an annularlyspaced arrangement and intended to engage a complementarily formedstepped arrangement carried thy the appliance 50. Thus the appliance 50,when mounted on the bent end portion 52, is locked in place againstrotation relative to the supporting member 36.

FIG. 4 illustrates a modification of the preferred embodiment whereinthe arms 30 and 38 carry an appliance holder 56 having a pin electricalplug 58 engagable with a socket 60 carried by the appliance 62. The plug58 has electrical leads 64 connected to an electrical conduit 66embedded in the supporting member 56 with a midportion supported in a`grommet 68 carried by one of the supporting arms 30. The conduit 66terminates at an electrical coupling '70. In this form of the invention,the appliance 62 is mounted on the sup-porting member 56 to complete anenergizing electrical circuit so that the appliance 62 can be rotated ina. variety of working positions without becoming entangled with theelectrical cords which supply the electrical cords which supply theelectrical energy.

FIGS. 5, 6 and 7 illustrate lstill another embodiment of the inventioncomprising an extensible supporting arm assembly generally indicated at72 and mounted on the underside of the supporting structure 16 bymounting means 74. The mounting means 74 is the same as the mountingmeans illustrated in the embodiment of the invention as shown in FIG. 1and includes the annular mounting plates 10 and 12 attached by threadedfasteners 14 to the structure 16. The adjustable locking ring 24 carriesa flat, resilient spring 26 and is engagalble with the fixer lockingring 23.

A circular mounting plate 76 is disposed within the aperture defined bythe plates 10 and 12 and has a plurality of fingers 78 slidably seatedin the annular slot defined by the plates 10 and 12 to permit the plate76 to rotate in an arc of 360. A downwardly depending lug 82 is carriedby the plate 76 and carries a pair of olppositely directed journals 84.

The extensible arm assembly 72 comprises a tubular inner arm section 86which is telescopically associated with a. tubular outer arm assembly88. The opposite side walls of the inner arm assembly 86 are engaged forpivotal movement to the journals 84 so that the arm section 86 may pivotbetween an upper substantially horizontal position to a downwardlygenerally vertical position. The inner arm section 86 has a lengthextending upwardly to provide an abutment surface 90. The abutment 90engages the spring 26 in the same manner as the arm sections 30 engagethe spring 26 to releasably lock rings 23 and 24 as illustrated in FIGS.1 and 2.

The outer arm assembly 88 is movable relative to the inner arm assembly86 between extenlded and retracted positions. A pin 92 at the free endof the arm assembly support-s a tool holder y94. The tool holder 94 isthen supported for rotation relative to an arm assembly 88.

A coil spring 95 is wrapped around one of the journals 84 with one end95A engaging the upper arm assembly 86 and its opposite end 95B reactingagainst a rpin 95C carried by the lug 82. This arrangement urges the armassembly 72 to a normal raised position where the appliance holder 94does -not interfere with the activities of the user. By applying aslight downward force on the appliance holder 94, it can be lowered toany selected working position.

It is frequently desirable that the appliance holder 94 maintain aconstant orientation relative to a fixed working surface in allpositions of the supporting arm assembly 72. For this reason a pair ofcooperating shaft sections 96 and 98 are provided. Shaft section 96 hasa narrowed section supported for rotation by a bearing 100 fixed to thearm section 88 and adjacent a rounded section 102 of the applianceholder 94. The shaft section 98 is journaled for rotation in a bearing104 fixed to arm section 86 adjacent the periphery of the lug 82. Theshaft sections 96 and 98 are locked in bearings 100 and 104 againstlongitudinal movement.

The shaft section 96 has a longitudinal and octagonal bore 106 runningfrom its inner end.

The shaft section 98 is milled with an octagonal cross section 108corresponding to the bore 106 of the companion shaft section 96.

The lengths of the bore 106 and the milled section 108 are such thatthey provide engagement of the shaft sections 96 and 98 between thefully extended and retracted positions of the arm sections 86 and thearm section 88.

A locking member 112 is carried on the inner side of the arm section 88and adjacent its inner end. The block 112 is provided with a bore 114which journals the end to shaft section 96. The locking member 112 has alateral threaded bore 118 to receive a threaded locking member 120,locking member 120 between a locking position wherein its inner endabuts one of the at surfaces of the shaft 98 and an unlocked positionwherein its inner end is slightly spaced from the shaft section 98 topermit relative longitudinal sliding movement between the shaft sections98 and 96.

The inner arm member 86 has a longitudinal slot 116 which as can best beseen in FIGURE 6 accommodates the locking member 112 when the armsections 86 and 88 are moved between extended and retracted positions.

A handle member 122 is fixed t0 the outer end of the threaded lockingmember 120 and provides means for applying a force to the locking member1'20 for rotation into or out of a locking position with shaft 98.

It can be seen that when the threaded member 120 is in its lockedposition, it not only prevents relative rotation between the shaftsections 96 and 98, but also locks the arm sections 86 and 88 againstlongitudinal movement. Thus the arm assembly 72 can be extended orretracted to a selected length and rigidly locked at that length.

The upper end of the shaft 98 carries a bevel gear 124 which meshes witha toothed section 126 formed adjacent the periphery of the lug 82.

When the arm sections 86 and 88 are pivoted between lowered and raisedpositions, the bevel gear 124 produces rotation of the companion shafts96 and 98.

The outer end of the shaft section 96 carries a similar bevel gear 128in mesh with a toothed section 130 formed adjacent the rounded section102 of the appliance holder 94. The toothed section 130 is identical tothe toothed section 126. Thus rotation of the shafts 96 and 98 producesa pivoting of the supporting member 94 about the pin 92.

The angular movement of the appliance holder 94 relative to thesupporting arm assembly 72 corresponds to the angular movement betweenthe supporting arm assembly 72 and the fixed lug 82. Thus the applianceholder 94 is always at a constant orientation relative to a fixedsurface as the arm assembly 72 moves between its raised and loweredpositions.

Although I have described two preferred embodiments of the presentinvention it is to be understood that various modications and revisionscan be made therein without departing from the spirit of the inventionas described in the scope of the claims.

I claim:

1. A supporting device for mounting a tool to a supporting structure,comprising:

(a) an elongated arm assembly;

(b) means on a first end of the arm assembly for mounting a tool;

(c) means for mounting the other, second end of the arm assembly -to asupporting structure for a first motion in which the first end of thearm assembly is movable in a circular path about an axis normal to thesupporting structure, and a second motion in which the first end of thearm assembly is movable toward and away from the supporting structurebetween a raised position and a lowered position;

(d) counterpoise means biasing the arm assembly so that its first end isurged toward its raised position, said counterpoise means beingoperative to suspend a tool mounted on a first end of the arm assemblywhen the first end is in its lowered position;

(e) means for restraining the motion of the arm assembly from a selectedorientation with respect to said normal axis comprising:

(l) a first locking member having a series of teeth formed about acommon center, and means for iixedly mounting said first locking memberso that its teeth are supported concentrically with respect to thenormal axis about which the arm assembly is movable in its first motion;

(2) a second locking member having a series of teeth engageable with theteeth of the first locking member;

(3) means for supporting the second locking member between the armassembly and the supporting structure for motion with respect to thefirst locking member between a first position in which the teeth of thetwo locking members are engaged to prevent rotation of the secondlocking member with respect to the first locking member about saidnormal axis, and a second position in which the second locking member isrotatable with respect to the first locking member about said normalaxis;

(4) means connecting the second locking member to the arm assembly sothat the lsecond locking member is fixed against rotation about saidnormal axis with respect to the arm assembly; and

(5) means on said arm assembly engageable with the second locking memberfor moving the second locking member to its first position as the firstend of the arm assembly is lowered from its raised position, and forallowing movement of the second locking member toward its secondposition when the first end of the arm assembly is in its raisedposition,

whereby the arm assembly can be swung with its first end in its raisedposition about said normal axis to a selected orientation with respectto said normal axis and then restrained in the selected orientation bymoving the first end of the arm assembly to its lowered position.

2. A supporting device as defined in claim 1, wherein said arm assemblycomprises a pair of telescopically associated arm sections including aninnermost and an outermost arm section interengaged for relativemovement between an extended length and a retracted length, andincluding mean for locking said arm sections one to the other with thefirst end of the arm assembly at a selected length from the mountingmeans for said arm assembly.

3. A supporting device as defined in claim 2, in which the means formounting a tool on the first end of the arm assembly include asupporting member carried at the free end of the outermost of said armsections and supported for pivotal movement relative to said outermostarm section, means on said supporting member providing a series of teethformed at a common radius about the axis of said pivotal movement, algear member meshed 'with said teeth, a shaft supporting said gearmember for rotation as the supporting member moves with respect to saidoutermost arm section; means journaling said shaft to said outermost armsection; and means for releasably locking said shaft against rotation sothat said supporting member may be locked in a selected relativeposition with respect to said voutermost arm section.

4. A supporting device as defined in claim 3, including a secondsupporting member having a series of teeth formed at a common radiusabout the axis of pivotal movement between the innermost arm section andsaid second .supporting member, a second gear member carried by saidshaft meshed with the teeth of said second supporting member, and meansfor fixedly supporting the second supporting member with the support sothat the first support member maintains a constant orientation with thesecond support member as the arm assembly is moved between its raisedand lowered position.

5. A supporting device as defined in claim 4, wherein said releasablelocking means compirses said shaft having a flat peripheral surface, athreaded member carried by one of said arm sections, said threadedmember being operable to engage said fiat surface to prevent rotation ofsaid shaft.

6. A supporting device as defined in claim 1, in which the mountingmeans for the arm assembly supports the first end of the arm assembly sothat its second motion is toward and away from a lowered position thatis below the second end of the arm assembly.

7. A supporting device as defined in claim 1, in which said arm assemblycomprises:

(a) a first member connected to the mounting for said arm assembly andprovided with a pair of spaced pivots;

(b) a pair of elongated arms each having upper and lower ends, the upperend of each of said pair of arms being connected to one of said pivotsso that each arm is movable about its respective pivot;

(c) a tool-supporting member;

(d) means providing a pivotal connection between the lower end of eachof said arms and said tool-supporting member so that said first member,said pair of elongated arms and said tool-supporting member form aparallelogram linkage; and

(e) means on one of the pivotal connections for locking one of the armsagainst motion with respect to the tool-supporting member so that thetool-supporting member can be locked in a selected position with respectto the first member.

8. A supporting device as defined in claim 7, wherein the last mentionedmeans comprises a pair of cooperating, interlocking elements forming oneof the pivotal connections between the tool-supporting member and thelower end of one of said arms, said interlocking elements havingportions for clamping the arm and the tool-supporting member together tolock them against relative movement.

9. A supporting device as defined in claim 8, wherein saidtool-supporting member has a coupling section for mating with acomplementarily formed coupling section carried by said tool for thetransmission of electrical energy through said tool-supporting memberand to said tool.

10. A supporting device as defined in claim 1, in which the first andsecond locking members comprise a pair of annular members each having aplanar series of teeth formed in an annular array, one of said annularmembers being adapted for a fixed attachment to the support structurewith its teeth facing away from the support structure, the secondannular member being supported adjacent the first annular member withits teeth confronting the teeth of the first annular member, and anelongated spring member spanning the second annular member with its endsengaged with opposite sides of the second annular member, and means onthe arm assembly engaged with the mid-section of the spring to bias thesecond annular member toward the first annular member.

11. A supporting device for mounting a tool to a supporting structure,comprising:

(a) a support adapted for attachment to a supporting structure;

(b) an elongated arm assembly formed of a pair of arm sectionstelescopically joined together for relative motion between extended andretracted positions;

(c) means for locking said arm sections together with one end of saidarm assembly at a selected distance with respect to the opposite end ofsaid arm assembly;

(d) means for pivotally connecting one end of said arm assembly to saidsupport so that the opposite end of said arm assembly can be movedbetween a raised position and a lowered position;

(e) a tool supporting member pivotally carried on the opposite end ofsaid arm assembly;

(f) means on said arm assembly connecting said toolsupporting member andsaid support so that said toolsupporting member maintains apredetermined orientation with respect to said support as the oppositeend of the arm assembly is moved between its raised and its loweredpositions; and

(g) counterpoise means for biasing the opposite end of the arm assemblytoward its raised position, said counterpoise means being operative tosuspend a tool carried on the tool-supporting member when the oppositeend of the arm assembly is in its lowered position.

12. The combination as defined in claim 11, in which the means forconnecting the tool-supporting member to the support comprises:

(a) an elongated shaft assembly including a pair of telescopicallyjoined shaft members connected to one another for rotation;

(b) means journaling one of said shaft members to one of said armsections and the other of said shaft members to the other of said armsections;

(c) rst gear means connecting one end of said shaft assembly to thetool-supporting member so that the tool-supporting member moves betweenpivoted positions with respect to said arm assembly as said shaftassembly is rotated; and

ing member can be supported at a selected distance from the support andis pivoted with respect to the arm assembly as the arm assembly ispivoted with respect to said support.

References Cited UNITED STATES PATENTS 510,147 12/1893 TarbOX 248-2811,685,718 9/1928 Murdoch 248-284 XR 2,648,146 8/1953 Foster.

ROY D. FRAZIER, Primary Examiner.

(d) second gear means connecting the opposite end of 15 I- FRANKLIN FOSSAssistant Examinersaid shaft assembly to said support so that the shaftassembly is rotated as the arm assembly is pivoted with respect to saidsupport whereby the tool-support- U.S. Cl. X.R.

